Forecasts

Depend On

Lots Of Luck

March 29, 1994|The New York Times

Meteorologists say that when it comes to predicting the random violence of severe storms and tornadoes, the most important forecasting tool is luck.

And in northern Alabama and Georgia, where several storm systems generated between 20 and 30 tornadoes on Sunday, "there was a lot of bad luck," said Joe Wheeler, a meteorologist in the Birmingham office of the National Weather Service.

The tornadoes were not particularly powerful, Wheeler said; they "just happened to hit the right spot."

They struck early in the day; tornadoes usually occur about 3 p.m. or 4 p.m., when the accumulated heat of the day causes rising air currents that become twisters. And the day happened to be Palm Sunday, when large groups had gathered in church buildings.

The tornadoes happened to travel on paths that included many of those buildings. And the county that took the greatest force of the storm, Cherokee County, Ala., is a poor, rural one without an extensive warning system.

Lee Helms, operation chief of the state Emergency Management Agency in Alabama, said progressively more severe storm alerts were issued on radio and television. "And there was a procedure by which firemen and policemen drive through with their sirens on."

The first indications of severe weather - a mass of very cold dry air running up against very warm, humid air - appeared on Saturday morning, said Jack Hales, lead forecaster at the Severe Storm Center, which monitors severe weather around the nation.

The center issued an "outlook for severe storms," a general alert extending over several states that is used by meteorologists when they prepare their weather forecasts.

The outlook was upgraded on Sunday morning to a "severe storm watch," which was broadcast on radio and television in parts of several states.

Wheeler said the storm watch became a "tornado warning" about 15 minutes before a tornado hit the Goshen Methodist Church in Piedmont, Ala., at the southern edge of Cherokee County, killing 20 people.

"Fifteen minutes is a long time," he said.

Tornadoes are most likely to strike from March through May, said Walter Zaleski of the National Weather Service.

In March 1984, 22 tornadoes slammed into the Carolinas, killing 57 people and injuring more than 1,200, he said.